OG11 阅读 第2篇-12题，多谢多谢了

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在做OG11的阅读，遇到麻烦了，OG11-2-12题，路过的同学们帮我看看吧，脑子转不过来……，谢谢大家了


A recent study has provided clues to predator-prey dynamics in the late Pleistocene era.
Researchers compared the number of tooth fractures in present-day carnivores with tooth fractures
in carnivores that lived 36,000 to 10,000 years ago and that were preserved in the Rancho La Brea
tar pits in Los Angeles. The breakage frequencies in the extinct species were strikingly higher than
those in the present-day species.
In considering possible explanations for this finding, the researchers dismissed demographic bias
because older individuals were not overrepresented in the fossil samples. They rejected
preservational bias because a total absence of breakage in two extinct species demonstrated that
the fractures were not the result of abrasion within the pits. They ruled out local bias because
breakage data obtained from other Pleistocene sites were similar to the La Brea data. The
explanation they consider most plausible is behavioral differences between extinct and present-day
carnivores-in particular, more contact between the teeth of predators and the bones of prey due to
more thorough consumption of carcasses by the extinct species. Such thorough carcass
consumption implies to the researchers either that prey availability was low, at least seasonally, or
that there was intense competition over kills and a high rate of carcass theft due to relatively high
predator densities.



12. The passage suggests that if the researchers had not found that two extinct carnivore species
were free of tooth breakage, the researchers would have concluded that
(A) the difference in breakage frequencies could have been the result of damage to the fossile
remains in the La Brea pits
(B) the fossils in other Pleistocene sites could have higher breakage frequencies than do the
fossils in the La Brea pits
(C) Pleistocene carnivore species probably behaved very similarly to one another with respect
to consumption of carcass
(D) all Pleistocene carnivores species differed behaviorally from present-day carnivore
species.
(E) predator desities during the Pleistocene era were extremely high
               


里面的逻辑关系…………我理不出来


如果研究人员没有发现：  两种灭绝的食肉动物没有牙齿的磨损，那么研究人员会得到的结论是


==>牙齿磨损的程度不同可能是在La Brea 的洞里对化石的损坏导致的


是说:       如果发现两种食肉动物的牙齿都有磨损，那么可能是在洞里对化石的磨损导致的?


解释：如果两种动物的牙齿都没有磨损，那么磨损几乎不可能是因为洞里的磨损导致的，因为如果是的话，那么他们应该呈现出相同的磨损程度。如果研究人员没有发现这样的两种动物，那么他们就可以排除因为洞穴的磨损而导致的牙齿磨损。


…………好绕啊，我翻译的对吗？谁能帮我精简一下思路，谢谢了，已经晕了……

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路过的同学们，帮我看看吧，捧个人场也是好的啊~~~~拜托了

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自己顶~~~

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……………………木有人理啊…………木有啊木有啊木有啊

aeoluseros

第二段里第二句：
They rejected preservational bias because a total absence of breakage in two extinct species demonstrated that the fractures were not the result of abrasion within the pits.
根据这两个extinct carnivore species，排除了“化石的保存问题”，如果没有这两个例子，就不能排除了，那么作者就可能认为保存问题可能是一个影响原因。那么肯定需要找一个与“保存”有关的选项
(A) the difference in breakage frequencies could have been the result of damage to the fossile remains in the La Brea pits
这句话描述的正是保存在LB堆里时候的损坏问题，也就是“保存问题”。正确答案。
翻译：坑坑洼洼数量的差异可能是因为LB堆里的化石受到损伤造成的。

原文第一段说了：Researchers compared the number of tooth fractures in present-day carnivores with tooth fractures
in carnivores that lived 36,000 to 10,000 years ago and that were preserved in the Rancho La Brea
tar pits in Los Angeles. The breakage frequencies in the extinct species were strikingly higher than
those in the present-day species.
这么长一句就表达一个意思“LB堆里面的化石是保存了几万年的，化石的牙齿坑坑洼洼相比现在很多”。

(B) the fossils in other Pleistocene sites could have higher breakage frequencies than do the fossils in the La Brea pits -->这个讲的是地点差异（location bias），与“保存”无关
(C) Pleistocene carnivore species probably behaved very similarly to one another with respect to consumption of carcass  --> 进食习惯，与“保存”无关
(D) all Pleistocene carnivores species differed behaviorally from present-day carnivore species.  --> 进食习惯，与“保存”无关
(E) predator desities during the Pleistocene era were extremely high  -->  猎食者密度，与“保存无关”

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aeoluseros ~~~  aeoluseros ~~~  aeoluseros ~~~  aeoluseros ~~~  aeoluseros ~~~  

多谢多谢~~~~

哈~~~